Khun Jerachai krub,
I just read the journal. They assigned hybrid status based on the intermediet range of morphological features then they look at the karyotype of the C. temensis, C. monoculus and the hybrids. They looked at the size of the chromosome, the NOR region and the C band. They found similarity in the NOR region (on the second pair chromosome in C. monoculus and on the third pair in C. tememsis). One group of hybrid had NOR on the third chromosome pair and another group had NOR on the second chromosome pair. The size of the chromosome also reviewed two distinct hybrid types. Anyhow, all of these suggested that they do hybridize. However, It did not prove that they were hybrids. They needed to be able to show that hybrids really came from two parent species which they did not prove that. Notice that in the conclusion they used the word "could" which is not a forcefully conclusion. In my humble opinion,they need to do further do sequence analysis in those two NOR regions or maybe look at the codominant expression nuclear genes and some mitochondrial genes to determine the hybrid status. Hope this helps krub.
In the Euryhaline species,
Anadromous fishes are fishes that are born in freshwater and later spent their life in saltwater and returned to freshwater to spawn. They are not saltwater fish by definition. The problem in some salmon (atleast in Oncorhynchus nerka and O. tshawytsha), there are some part of the population that does not spent their life in the ocean (saltwater) at all so they are definitely different from saltwater fishes. Catadromouse fishes in the opposite of that. The euryhaline fishes are definitely on their own catagory.
เข้ามาอ่านกระทู้ของน้า จิรชัย แล้วผมเหมือนหลุดจากกะลาเรื่องปลาเลยครับ ได้ความรู้เพียบจริงๆ ที่บ้านมีปลาหมอสีอยู่ตัวเดียว ตัวต่อไปอยากได้ กระทิงไฟมาเลี้ยงมั่ง ขอบคุณสำหรับความรู้ครับ 
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